  .show{
    position: fixed;z-index: 1000; 
    left: -4000px;
    background-color: aliceblue;
  }

  .show.left::before,.show.left::after{
    content: "";
    // border-width: 8px 8px 8px 8px;
    // border-color: transparent transparent #001529 transparent;
    // border-style: solid;
    border: solid transparent;
    display: block;
    position: absolute;
  }
  .show.right::before,.show.right::after{
    content: "";
    // border-width: 8px 8px 8px 8px;
    // border-color: transparent transparent #001529 transparent;
    // border-style: solid;
    border: solid transparent;
    display: block;
    position: absolute;
    left: 96%;
  }
  .show.left::before,.show.right::before{
    border-width: 8px;
    border-bottom-color: #E8E8E8;
    top: -15px;
  }
  .show.left::after,.show.right::after{
    border-width: 8px;
    border-bottom-color: #FAFAFA;
    top:  -14px;;
  }
